This is the core of your write-up. Explain the "Aha!" moment:
If the video looked normal, did you check the audio track? Mention if you used Audacity or Sonic Visualizer to look at the Spectrogram for hidden text.
A quick summary of the trick (e.g., "The flag was hidden in the LSB of the audio channel"). 3137.mp4
Did you run exiftool 3137.mp4 ? Often, flags or hints are hidden in the "Comment" or "Artist" tags.
Use file 3137.mp4 to confirm it is actually an MP4 and not a renamed archive or polyglot file. This is the core of your write-up
If you found something in a single frame, explain how you extracted it using ffmpeg -i 3137.mp4 -vf "select=eq(n\,3137)" -vframes 1 out.png .
List your toolkit, such as ExifTool , FFmpeg , StegSolve , Sonic Visualizer , or Strings . 2. Initial Analysis Describe your first steps after receiving the file: A quick summary of the trick (e
Briefly state what the goal was (e.g., "Find the hidden flag within the video file").